Neurogenesis of excitation-contraction uncoupling in aging skeletal muscle.

Excitation-contraction (EC) uncoupling is a major cause of decreased muscle force generating capacity (specific force). However, the underlying mechanisms of EC uncoupling in muscle from aging mammals have not been characterized. We propose that impaired motor neuron function with aging leading to muscle denervation, a process probably initiated earlier than detected by in vitro morphologic techniques, results in EC uncoupling.